Information handling system predictive key retraction and extension actuation

ABSTRACT

An information handling system integrated keyboard selectively retracts and extends keys based upon detected conditions, such as housing configuration, housing motion and end user indications. Extension and retraction shuttle plates motivated by actuator wires moves a sliding plate to extended and retracted positions that define the key positions. Nickel titanium alloy actuator wires shorten upon application of current to pull the shuttle plates to the extended or retracted positions that are maintained by a lock. Limit switches remove current at detection of a desired shuttle plate position. One or more controllers manage actuator wire operation based upon detected conditions and actuator wire temperature and electrical characteristics.

CROSS REFERENCE TO RELATED APPLICATIONS

U.S. patent application Ser. No. 15/800,810, entitled “InformationHandling System Integrated Device Key Actuator” by inventors Jason S.Morrison. Adolfo S. Montero. and Laurent A. Regimbal, filed on even dateherewith, describes exemplary methods and systems and is incorporated byreference in its entirety.

U.S. patent application Ser. No. 15/800,829, entitled “InformationHandling System Integrated Device Actuator Monitoring” by inventorsJason S. Morrison and Mark S. Sears, filed on even date herewith,describes exemplary methods and systems and is incorporated by referencein its entirety.

BACKGROUND OF THE INVENTION Field of the Invention

The present invention relates in general to the field of portableinformation handling system management, and more particularly to aportable information handling system predictive key retraction andextension actuation.

Description of the Related Art

As the value and use of information continues to increase, individualsand businesses seek additional ways to process and store information.One option available to users is information handling systems. Aninformation handling system generally processes, compiles, stores,and/or communicates information or data for business, personal, or otherpurposes thereby allowing users to take advantage of the value of theinformation. Because technology and information handling needs andrequirements vary between different users or applications, informationhandling systems may also vary regarding what information is handled,how the information is handled, how much information is processed,stored, or communicated, and how quickly and efficiently the informationmay be processed, stored, or communicated. The variations in informationhandling systems allow for information handling systems to be general orconfigured for a specific user or specific use such as financialtransaction processing, airline reservations, enterprise data storage,or global communications. In addition, information handling systems mayinclude a variety of hardware and software components that may beconfigured to process, store, and communicate information and mayinclude one or more computer systems, data storage systems, andnetworking systems.

Portable information handling systems typically integrate input/outputsystems and a power source to support use of the system without anyfixed resources, such as external peripherals and power. For example,convertible information handling systems typically have main and lidportions rotationally coupled to each other to open for use and closefor portability. A typical convertible information handling systemintegrates a display in the lid housing portion that presents visualimages to an end user. Processing components disposed in the mainhousing portion generally process information to create visualinformation for presentation to a user at the display. For example, acentral processing unit (CPU) executes instructions to generate visualinformation that a graphics processing unit (GPU) processes into pixelvalues for generation of visual images at the display. An end userinteracts with the information handling system through the visualimages, such as by inputting information through a touchscreen, mouse orkeyboard. A typical convertible information handling system integrates akeyboard and touchpad in the upper surface of the main housing so thatan end user can make inputs when the lid housing portion rotates to anopen position and exposes the main housing portion upper surface. Whenthe lid portion rotates approximately ninety degrees, the display isheld in a viewing position with the keyboard arranged to accept inputs.In some embodiments, the lid portion rotates 360 degrees to a tabletconfiguration that allows an end user to more comfortably interact witha touchscreen to make inputs.

Generally, portable information handling system dimensions are driven bythe size of the display integrated in the portable housing. Portableinformation handling systems with larger displays tend to have more roomto integrate more powerful processing components and larger storagedevices, such as solid state drives (SSD) and additional random accessmemory. As display size shrinks, typically performance tradeoffs aremade due to the reduced room within the housing to fit in the processingcomponents. However, even in portable systems that have large displays,end users typically desire to have housings with minimal heightdimensions and weight. Information handling system manufacturersminimize system height by selecting low profile components and usingcare in component placement within the housing so that adequate coolingis available.

A keyboard integrated into a housing offers convenience with the abilityto more readily perform inputs when an end user is on the go. Generally,typed inputs made at a keyboard with physically-moving keys providefeedback to the end user that makes information handling systeminteractions more user friendly. However, physically-moving keys tend toadd vertical height to the information handling system so that the keyshave sufficient room to move up and down. Often the keyboard keys arebuilt into a recess formed in the upper surface of the main housingportion so that the lid housing portion can rotate to a closed positionover the keys. One alternative for reducing vertical height of aportable system having an integrated keyboard is to reduce the amount ofkey travel supported by the keys, however, reducing key travel changesthe end user experience and tends to decrease input speeds and accuracy.Another alternative for reducing portable system height with anintegrated keyboard is to retract the keys into the portable housingwhen closing the system lid housing portion. A difficulty withretraction of keys is that a mechanical or electromechanical actuatorthat typically retracts and extends the keys tends to add size andpresents a point of failure after repeated uses. For example, aretraction mechanism typically must overcome a key biasing mechanismthat bias keyboard keys upward, which tends to create mechanical stressthat wears both the retraction and biasing mechanisms.

SUMMARY OF THE INVENTION

Therefore, a need has arisen for a system and method which retracts andextends keyboard keys in an automated manner with a minimal heightstructure.

A further need exists for a system and method which manages currentapplication to actuate shape memory wire for retracting and extendingkeyboard keys in a repeatable manner.

A further need exists for a system and method which monitors currentapplied to actuate shape memory wire for correct temperaturetransitions.

In accordance with the present invention, a system and method areprovided which substantially reduce the disadvantages and problemsassociated with previous methods and systems for retracting andextending keyboard keys of an information handling system. Currentapplied to shape memory wire actuates keyboard retraction and/orextension with a low height structure. Rapid and reliable motion inducedby shape memory wire contraction slides a plate relative to the keyboardto retracted and extended positions maintained between actuations withbistable retracted or extended states. For example, “maglev” keys biasto the extended or retracted positions based upon keyboard sliding plateorientation. Alternatively, a lock or latch maintains the keyboardsliding plate configuration to overcome key biasing devices, such asrubber domes. A keyboard manager/controller applies current based upondetected conditions and manages current application to ensure desiredkeyboard behavior with reduced wire wear.

More specifically, an information handling system processes informationwith processing components disposed in a housing, such as a housinghaving main and lid portions rotationally coupled to each other. Forexample, a processor and memory in the main portion cooperate to executeinstructions that generate visual information presented on a displayintegrated in the lid portion. An end user interacts with the visualinformation through a keyboard, such as a keyboard integrated in themain housing portion upper surface. A keyboard manager monitorsconditions related to the keyboard to selectively retract and extend thekeyboard keys by applying current to actuator wires. For example, afirst set of plural actuator wires shorten in response to application ofcurrent to pull a first shuttle that slides a plate relative to the keyboard from an extended to a retracted position, where a magnet latchholds the plate in place. For instance, with “maglev” keys, the plateinteracts with the keys to change an upward bias to a downward bias andpull the keys in. Alternatively, with a rubber dome upward biasingdevice, the plate actuation overcomes an upward bias of the rubber domesand pull the keys into the main housing portion to be held in place witha magnet latch or similar device. A second set of plural actuator wiresshorten in response to application of current to pull a second shuttlethat slides a plate relative to the keyboard to an extended positionthat changes the downward bias to an upward bias to lift the keys upwardand out of the housing. Alternatively with rubber dome key biasing, theplate releases the keys to bias upward and out of the main housingportion. The keyboard manager monitors actuator wire current,temperature, resistance and position to achieve desired retracted andextended positions. For example, actuator wire resistance is sampledbefore application of actuation current to ensure wire continuity andanticipated heating. Actuator wire temperature is sampled to detecttransitions between austensite and martensite phases that trigger wireshortening and return to pre-heating length. For example, application ofcurrent to actuator wires is restricted so that actuation of keys in onedirection does not pull on actuator wires for the other direction untila phase change to a greater length has taken place. For instance,housing portion rotation is monitored for relative position and rate ofchange so that keyboard key actuation occurs as needed by the end userwithout unnecessary or excessive actuation wire use.

The present invention provides a number of important technicaladvantages. One example of an important technical advantage is that aninformation handling system keyboard's keys are rapidly and efficientlyretracted into the information handling system housing with anintegrated structure having minimal height. Retraction and extensionshuttles couple to retraction and extension actuator wires thatselectively shorten to pull the shuttles relative to the keyboard. Theshuttles engage a sliding plate, such as through a shoulder screw orother engagement point, which interacts with the keys to retract orextend the keys in a rapid, predictable manner with minimal movingparts. Upon reaching a desired extension or retraction location, thesliding plate locks in place, such as with a magnetic locking devicethat is overcome by a subsequent actuator wire movement. In oneembodiment, the sliding plate and actuator wire assembly has a height ofless than key travel so that overall impact of including the keyretraction structure is to reduce the height of the information handlingsystem since retraction of the keys in a closed configuration results ina reduced total height of the main housing. Actuator wires made of shapememory alloys, such as nickel titanium, endure repeated actuations tooffer a robust system readily monitored through the electrical andphysical properties of the wires, such as resistance and temperaturechanges in response to current application. Rapid reactions initiated bycurrent application to the actuator wires provides preciseimplementation of key extensions and retractions based upon detectedconditions for an excellent user experience.

BRIEF DESCRIPTION OF THE DRAWINGS

The present invention may be better understood, and its numerousobjects, features and advantages made apparent to those skilled in theart by referencing the accompanying drawings. The use of the samereference number throughout the several figures designates a like orsimilar element.

FIG. 1 depicts an exploded view of an information handling system havinga keyboard with keys retracted and extended by a keyboard manager;

FIG. 2 depicts a bottom view of a keyboard having keyboard extension andretraction managed by actuation wires;

FIGS. 3A, 3B and 3C depict side cutaway views of a keyboard key in anextended position, an input position and a retracted position;

FIGS. 4A, 4B, 4C, and 4D depict side cutaway views of a keyboard keyactuated between extended, intermediate and retracted positions toprovide normal, ruggedized and stored key positions;

FIG. 5 depicts a block diagram of an information handling system havingkey retracted and extended positions initiated in response to detectedconditions;

FIG. 6 depicts a flow diagram of a process for managing keyboard keypositions;

FIG. 7 depicts a flow diagram of a process for operational monitoring ofconditions at an information handling system to manage key extension andretraction;

FIG. 8 depicts a block diagram of an information handling systemkeyboard key position manager;

FIG. 9 depicts a circuit block diagram of an actuator wire circuitprotected by a resistance sampling circuit; and

FIG. 10 depicts a circuit block diagram of both retraction and extensionactuator wire sets protected by a common resistance sampling circuit.

DETAILED DESCRIPTION

An information handling system keyboard's keys retract and extend withapplication of current to actuator wires based upon detected conditions.For purposes of this disclosure, an information handling system mayinclude any instrumentality or aggregate of instrumentalities operableto compute, classify, process, transmit, receive, retrieve, originate,switch, store, display, manifest, detect, record, reproduce, handle, orutilize any form of information, intelligence, or data for business,scientific, control, or other purposes. For example, an informationhandling system may be a personal computer, a network storage device, orany other suitable device and may vary in size, shape, performance,functionality, and price. The information handling system may includerandom access memory (RAM), one or more processing resources such as acentral processing unit (CPU) or hardware or software control logic,ROM, and/or other types of nonvolatile memory. Additional components ofthe information handling system may include one or more disk drives, oneor more network ports for communicating with external devices as well asvarious input and output (I/O) devices, such as a keyboard, a mouse, anda video display. The information handling system may also include one ormore buses operable to transmit communications between the varioushardware components.

Referring now to FIG. 1, an exploded view depicts an informationhandling system 10 having a keyboard 34 with keys 68 retracted andextended by a keyboard manager 42. In the example embodiment,information handling system 10 is a portable system having a convertibleconfiguration that rotates between a closed position and a variety ofopen positions, such as with 90 degrees of rotation to a clamshellorientation or 360 degrees of rotation to a tablet configuration. A mainhousing portion 12 provides a base that contains processing componentsto process information. A lid housing portion 14 integrates a display 38and rotationally couples to the main housing portion with a hinge 36 tosupport rotation of the housing portions relative to each other. In theexample embodiment, the processing components include a motherboard 16coupled to main housing portion 12 and supporting communication betweena central processing unit (CPU) 18 and random access memory (RAM) 20.Processor 18 executes instructions in cooperation with RAM 20, such asinstructions associated with an operating system and applications storedin persistent memory, such as a solid state drive 22. Informationgenerated by processor 18 is provided to a graphics processor unit (GPU)24 to generate pixels values that define visual images presented atdisplay 38. A chipset 28 having a variety of processors, controllers andfirmware manages physical interactions between the processingcomponents, such as to provide networking through a wireless networkinterface card (WNIC) 30. An embedded controller 26 manages power andinput/output device interactions, such as inputs made by and end user atkeyboard 34 or other devices, such as a touchpad or mouse. The exampleembodiment depicts a portable information handling system havingrotationally coupled housing portions, however, alternative embodimentsmay include other types of configurations, including a peripheralkeyboard that separates from an information handling system.

In the example embodiment, a main housing portion upper surface 32covers the processing components and integrates keyboard 34 havingselectively retractable keys 68. With lid housing portion 14 rotated toa viewing position, such as 90 degrees of rotation relative to mainhousing portion 12, keys 68 extend upwards to accept end user keyedinputs. To make an input, an end user presses on a key 68 to depress thekey into main housing portion 12 and contact a sensor that detects theinput. During normal operations, keys 68 bias upwards and provideresistance against input presses so that an end user has a naturalfeedback when typing at keyboard 34. As lid portion 14 rotates to aclosed position over top of keyboard 34, all of keys 68 retract into theinterior of main housing portion 12 so that keys 68 do not preventclosing of lid housing portion 14 against upper surface 32. Byretracting keys 68 into main housing portion 12, less height is consumedfor keyboard 34 integration into information handling system 10,resulting in a shorter and lighter weight system. In the exampleembodiment, a rotation sensor 40 tracks rotational movement of hinge 36and reports the movement to a keyboard manager 42. Keyboard manager 42applies the movement to determine whether to retract or extend keys 34.For example, rapid rotation from an open to the closed positions of thehousing portions initiates key retraction at a larger angle than moreslow rotation so that keys 34 retract with sufficient time to enter intomain housing 12 before lid housing portion 14 hits keys 34. As anotherexample, rotation from a closed position towards an open positiondetected by rotation sensor 40 allows keyboard manager 42 to wait untila stabilized housing portion configuration is reached with the stoppingof rotation before extending keys 34. In the example embodiment,keyboard manager 42 executes embedded code as a dedicated controller,however, in alternative embodiments functional control by keyboardmanager 42 may include instructions executed across a variety ofhardware devices, such as an embedded code module executing on embeddedcontroller 26. Additional example embodiments and keyextension/retraction conditions are set forth in greater detail by theexamples set forth below.

Referring now to FIG. 2, a bottom view depicts a keyboard 34 havingkeyboard extension and retraction managed by actuation wires 56. In theexample embodiment, an extension shuttle 46 actuates to place thekeyboard keys in an extended configuration and a retraction shuttle 48actuates to place the keyboard keys in a retracted configuration.Extension shuttle 46 couples to three actuation wires 56 with eachactuation wire connected to a keyboard manager circuit board 60 that hasa fixed position relative to the keyboard 34. Each actuation wire wrapsin a loop around an actuation wire anchor 62 integrated in extensionshuttle 46. One end of each actuation wire provides a current connectionand the other end provides a ground so that a current passed fromkeyboard manager circuit board 60 runs to ground resulting in heating ofthe actuation wire. A keyboard manager controller 58 provides current tothe three actuation wires 56 when key extension is desired. As actuationwires 56 heat, shape memory material of the wire, such a nickel titaniumalloy material, transitions from martensitic to austenitic phaseresulting in a shortening of the length of the wire. The shorter lengthof actuation wires 56 pulls extension shuttle 46 towards keyboardmanager circuit board 60 providing motion that frees keys of keyboard 34to extend. Retraction shuttle 48 is controlled in a similar manner butopposite direction so that motion of retraction shuttle 48 providesmotion to retract keys of keyboard 34.

In the example embodiment, actuation wire anchors 62 are formed as loopsthat effectively act like a pulley to draw motion of the shuttle onshortening of the wire. For instance, each shuttle has three actuationwire anchors heat staked to it to support three actuation wires. Controlfor managing actuation of each shuttle is, as an example, passed from anembedded controller through the keyboard flexible circuit connector 64and then to keyboard manager controllers 58. Motion of shuttles 46 and48 are translated to the keys through a sliding plate 78 that couples tothe bottom of keyboard 34 and slides between the separated keyboardmanager circuit boards 60. As a shuttle is activated into motion by itsset of actuation wires, the shuttle pulls on sliding plate 78 atshoulder screws 52 or other contact points so that the sliding plateacts to retract or extend keyboard 34 keys. A magnet lock 66 releasessliding plate 78 during activation of a shuttle and then re-engagessliding plate 78 once shuttle-induced motion is completed so thatsliding plate 78 stays in the position to which shuttle actuation movedit. Once shuttle 46 or 48 has completed an actuation, a return spring 50coupled between shuttles 46 and 48 bring both shuttles to a neutralposition. In the example embodiment, each shuttle has three actuationwires 56 that shorten to a similar length to provide a uniform pullacross the shuttle. In alternative embodiments, more or less wires maybe used with different types of routing. For example, a larger loop areaon the shuttle provides for a long actuation wire with additionalmovement provided during shortening. Alternatively, sliding plate 78 mayslide longitudinally instead of laterally with actuation wires 56aligned perpendicular to those of the depicted example embodiment.

Referring now to FIGS. 3A, 3B and 3C, side cutaway views depict akeyboard key 68 in an extended position, an input position and aretracted position. FIG. 3A depicts key 68 in an extended positionbiased upwards and away from a detection sensor 76 by a rubber dome 72.A scissors structure 70 guides vertical movement of key 68 during apress by an end user, such as to make an input. Rubber dome 72 providesan upward bias that the end user overcomes during an input so that key68 makes contact with detection sensor 76 to indicate an input. FIG. 3Billustrates that scissors structure 70 rotates at one end about a fixedcoupling location 72 and slides relative to the detection sensor at aslideable coupling location 74 so that contact is made with thedetection sensor 76. FIG. 3C illustrates an example embodiment in whichsliding plate 78 engages slideable coupling location 74 to pull key 68to the retracted position. Sliding plate 78 slides in the direction ofslideable coupling location 74 so that a member extending upwards fromsliding plate 78 engages with scissors 70 to pull scissors 70 to theretracted position. Sliding plate 78 has movement initiated byapplication of current to the actuator wires and is then locked in placeto hold scissors 70 in the retracted position. The upward bias of rubberdome 72 can return key 68 to an extend position if sliding plate 78 isreleased, however, in the example embodiments a separate actuator wireinitiation pulls sliding plate towards fixed coupling location 72 torestore key 68 to the extended position. In alternative embodiments, key68 may be biased upwards with other types of biasing devices than rubberdome 72 and alternative guiding structures may be used instead ofscissors 70 to guide key motion. Actuation of actuator wires withcurrent provide movement to lock and release the keys in various otherembodiments by pulling keys to the desired position and locking the keysin place after the actuation.

Referring now to FIGS. 4A, 4B, 4C, and 4D, side cutaway views depict akeyboard key actuated between extended, intermediate and retractedpositions to provide normal, ruggedized and stored key positions. FIG.4A depicts an alternative scissors structure 70 that guides key 68during vertical travel and provides an upwards bias, such as with aspring mechanism integrated in scissors 70 or a “maglev” device. Forexample, opposing magnet polarities in key 68 and keyboard 76 bias key68 upwards to an extended position. FIG. 4B illustrates that a press onkey 68 results in an input once key 68 travels past a primary switchheight 80, roughly at contact with a gasket 82. FIG. 4C illustrates anintermediate position of key 68 established by actuation of an actuationwire to partially move and then lock the sliding plate. For example,moving the “maglev” opposing polarity magnets to align in polaritybrings key down from the extended to the intermediate position. At theintermediate position, key 68 contacts gasket 82 to provide a ruggedizedsolution that prevents water or contaminants from entering outside ofkey 68 an into the information handling system. As illustrated by FIG.4D, a secondary detection device switch height 84 provides a key inputdetection as gasket 82 compresses, thus maintaining a ruggedizedconfiguration while accepting key inputs with reduced vertical motion ofkey 68. In the example embodiment, multiple sets of actuator wires maybe used, such as a first set to maintain the intermediate position ofFIG. 4C and a second set to maintain the compressed position of FIG. 4D.Alternatively, the intermediate position illustrated by FIG. 4C may beused to retract keys 68 for storage with some room left between thehousing portions in the closed position to allow some extension of keys68. In alternative embodiments, different sets of actuator wires may beused to establish multiple key heights and may set key heights in pluralsets of keys so that only some keys are retracted in response to anactuation. Further, key retraction to the ruggedized mode depicted byFIG. 4C may be supported in an automated manner, such as in response todetection of liquids or other contaminants. Advantageously, with magnetlevitated key bias, the magnet devices operate to maintain the slidingplate in positions.

Referring now to FIG. 5 depicts a block diagram depicts an informationhandling system having key retracted and extended positions initiated inresponse to detected conditions. In the example embodiment, keyboardmanager 42 executes as embedded code on an embedded controller havingGPIO's to plural sensor devices. Rotation sensor 40 provides therelative rotational orientation of housing portions, such as a lid andmain housing portion of a portable system. Rotation sensor 40 maymeasure the relative position or an axle that supports the housingportion rotation or may measure accelerations, such as with anaccelerometer configured as a gyroscope that determine angularorientations relative to gravity. A rate of rotation of the housingportions may be detected and reported by the rotation sensor ordetermined by keyboard manager 42 based upon changes in reported angularorientations over time. Keyboard manager 42 manages key retraction andextension based upon angular orientation of the housing portions andrate of rotation of the housing portions. For example, if housingportion rotation is detected and keyboard keys are retracted, thenkeyboard manager 42 awaits for motion of the housing portions to stopbefore determining whether to extend the keys. For instance, a usertypically uses both hands to rotate the housing portions and cannot makeintentional keyed inputs while housing portions are rotated, so keyextension can wait until motion is complete and the keys are disposed ina configuration that accepts typed inputs. After motion is complete,such as when rotation sensor 40 detects a fixed housing portionrotational orientation, keyboard manager 42 analyzes sensed conditionsto determine if the keys should extend. For instance, if a clamshellorientation is detected the keys extend, however, if a tabletconfiguration is detected, the keys remain retracted so that thekeyboard may rest on a surface without having keys extended.

Similar analysis applies when keyboard keys are extended and a userrotates housing portions from an open to a closed position. Keyboardmanager 42 will seek to have keyboard retraction occur before keys comeinto contact with the lid housing portion, however premature keyretraction could result in an end user halting housing portion rotationbefore closing so that that the end user can make inputs. In such asituation, multiple actuations of the actuator wires may result inexcessive heating or wear. For example, if actuation to retract keys isquickly followed by actuation to extend keys, the retraction actuatorwires may not cool adequately to allow a phase change and wirelengthening so that the extension actuator wires will pull againststill-shortened retraction actuator wires. In one embodiment, a minimumtime period must pass between applications of current to an actuatorwire before another actuation may take place, such as a two second timeperiod. To avoid such situations, retraction of keys upon closing occurswith rotation still in progress and includes analysis of the rate ofclosing of the housing portions.

Other types of conditions may be analyzed when determining if keysshould be retracted or extended. As an example, an actuation button 86accepts a manual end user input to actuate the keys from a currentretracted or extended position to the opposite condition. As otherexamples, a touch sensor 88, voice sensor 90 or gesture sensor 92 acceptend user inputs to define key positions. An air moving device 94interfaced with keyboard manager 42 provides active cooling airflow tothe actuator wires after actuation that allows a more rapid cooling andtransition of wire material phase to a lengthened state. Some examplesof air moving devices include piezo fan, a piezo blower, a piezo coolerand an electrostatic air mover that uses ionic wind. Generally, such airmoving devices vibrate a physical device at a resonant frequency for ashort time period to generate air motion. Other types of coolingairflows may also be generated, such as by re-directing system coolingfan airflow for a temporary time period. In one embodiment, actuation ofthe actuator wires may store mechanical or electric potential energythat is released as a cooling airflow after current is turned off at theactuator wires. Temporary application of a cooling airflow more quicklyreduces actuator wire temperature so that subsequent applications ofcurrent may take place with a reduced time delay. The actuator wirecooling may be automatically initiated when a physical position changeof the sliding plate is detected, such as by triggering a temporaryapplication of power to an air moving device up detection of movement bya limit switch. In one alternative embodiment, a spring loaded fanimpeller wound up by movement of the sliding plate releases afteractuation to generate a short burst of cooling airflow. Alternatively, apiston charges by motion of the sliding plate to release a coolingairflow after movement is complete.

Referring now to FIG. 6, a flow diagram depicts a process for managingkeyboard key positions. The process starts at step 96 with theinformation handling system in a power off state having keyboard keysretracted. At step 98, the keyboard monitors for a transition to a poweron state and, when a power on state is detected, proceeds to step 100.At step 100 a determination is made of whether the information handlingsystem has a lid housing portion rotated to an open position so that thekeys remain retracted until the housing lid rotates to an open positionthat exposes the keys for use by an end user. At step 102, once the keysare exposed with the lid in an open position, a determination is made ofwhether an end user is signed into the information handling system. Ifthe end user is signed in, the process continues to step 112 toestablish the keys as retracted or extended based upon operationalmonitoring conditions. At step 104 with the lid housing portion rotatedopen to expose the keys and the end user not signed in, the keys extendso that the end user may sign in. If at step 106 a successful sign inoccurs, the process continues to step 112 for operational monitoring. Ifno sign in occurs, the process continues to step 108 to monitor for apower off of the information handling system. Once a power off isdetected, the process continues to step 110 to retract the keys.Similarly at step 112, during operational monitoring, at step 116monitoring determines if a power off of the information handling systemtakes place and, if so, the keys retract. Power off that results in keyretraction may include a user selected power off, an automatedpower-saving power off, or a low battery condition so that the keysretract before the system shuts off due to a low battery.

Referring now to FIG. 7, a flow diagram depicts a process foroperational monitoring of conditions at an information handling systemto manage key extension and retraction. The process starts at step 118with measurement of the housing rotational position and step 120 withthe measuring of housing rotational rate. In various embodiments othertypes of sensed conditions and sensors are used, such as a camera towatch end user interactions, a touch sensor to monitor user touches, abattery gauge to monitor system charge, the number and types ofapplications running on the system, the active selected application,screen timeout, wireless signals, etc. . . . . In one alternativeembodiment, accelerometers measure housing portion rotational angles; insuch a system, if accelerometer data becomes compromised as may happenwhen a system is held in a portrait orientation, key retraction may beimplemented to ensure that damage will not occur to the keys if housingportions are closed while rotational orientation cannot be adequatelydetermined. At step 122 a determination is made based upon the sensedconditions whether to change the key positions. If not, the processcontinues to monitor conditions. If a determination is made to changekey positions, the process continues to step 124 to measure thetemperature of the actuator wires and compare the measured temperatureagainst defined limits. For instance, if a measured temperatureindicates that an actuator wire is in a shortened state, then applyingcurrent to an opposing wire may result in system damage. As anotherexample, a minimum cool down temperature may be enforced for theactuator wires after an actuation to help preserve the life of theactuator wire material. In some embodiments, a minimum time is enforcedbetween actuations to help ensure adequate wire cooling. If thetemperature of the actuator wire exceed a threshold, the process returnsto step 122 to continue to check if a key position change is neededuntil the temperature of the actuator wires come into limits. At step126 hysteresis is checked to ensure that the pending actuation does notfollow too closely to a preceding actuation, such as might happen if auser rapidly reverses the direction of the housing rotation. Forexample, key retraction may have a reduced time delay from a previousactuation so that keys are not impacted if a housing closes over them,while some delay for key extension may be acceptable after a housingcompletes rotation to an open position. At step 128 current is appliedto the appropriate set of actuator wires to implement a key retractionor extension. In essence, the keyboard manager predicts based uponavailable sensed inputs the key behavior desired by an end user andplaces the keys in the desired state while reducing unneeded orundesired actuations that wear on the key actuation system.

Referring now to FIG. 8, a block diagram depicts an information handlingsystem keyboard key position manager 42. In the example embodiment,keyboard manger 42 monitors three physical conditions to determinewhether to apply current that actuates the actuator wires. A temperaturesensor 130 measures actuator wire temperature to determine the phases ofthe actuator wire so that current is not applied while one or moreactuator wires are in a shortened state. In particular, if an actuatorwire for actuation is one direction is in a shortened state, applicationof current to actuator wires in an opposite direction may cause physicaldamage to the key actuation system as shortened actuator wires workagainst each other. In one alternative embodiment, keyboard manager 42monitors temperature to control application of a cooling airflow overthe actuator wires, such as with an air moving device aligned to directcooling airflow across the actuator wires. In addition to checkingactuator wire temperature, keyboard manager 42 checks the resistanceacross the actuator wires to ensure that current applied to the actuatorwires is not grounded or sent across an open circuit. For example,before sending an actuation current that will heat the actuator wires,keyboard manager 42 sends a measuring current across the actuator wiresand compares the current at the opposing end of the actuator wire withthe applied current to determine if an expected resistance exists.Excessive resistance may indicate, for example, a failed or failingactuator wire that does not adequately carry current across its length.Insufficient resistance may indicate a broken wire in contact withground or a grounded component that has come loose and into contact withthe actuator wires. An advantage of measuring resistance across actuatorwires is that the wires themselves may be implement without insulation.

By measuring actuator wire temperature and resistance before applyingcurrent to the actuator wires, keyboard manager 42 reduces the risk ofdamage associated with an inappropriate actuation, however, additionalmonitoring of conditions during actuation provides further safeguardsagainst system damage. For example, during actuation as current isapplied to actuator wires, keyboard manager 42 monitors temperature toensure that an expected rise in temperature is experienced. If, afteractuation current is applied, an expected rise in temperature is notexperienced within a time limit, actuation current is removed so thatactuator wire resistance may be checked again. In addition, positionmonitoring devices monitor key actuation structures for movement toensure that adequate movement has taken place. For example, linearresistor sensors or potentiometers disposed along the sliding platedetect movement and compare detected movement with expected movement toensure that actuation has taken place. In various embodiments, varioustypes of movement sensing devices may report sliding plate movement inresponse to actuation, such as a Hall sensor and magnet on opposingmoving portions or other types of limit switches. Since the shape memoryactuation wires provide actuation at phase change in a rapid manner atdefined temperatures, active monitoring of actuator wire temperature andsliding plate movement provide precise control points at which actuationcurrent may be modified or shut off. That is, if an expected temperaturerise and resistance exist at the actuator wires, cutting off current inthe absence of movement may prevent system damage due to binding orother interference that prevents key actuation.

Referring now to FIG. 9, a circuit block diagram depicts an actuatorwire circuit 56 protected by a resistance sampling circuit 132. In theexample embodiment, a key actuator drive circuit 136 has a firstactuator wire set 56 that provides key retraction and a second actuatorwire set 56 that provides key extension. Each actuator wire set 56 ismonitored by its own resistance sampling circuit 132 that is isolatedfrom drive circuit 136. Before drive current is applied to actuatorwires 56, the resistance monitoring circuit 132 associated with theactuator wire set checks the resistance of the actuator wires, such asby applying a test current and comparing voltages. In alternativeembodiments, other types of resistance measurements may be taken. Themeasured resistance is compared against an acceptable range to ensurethat application of current to the actuation circuit will provide thecorrect heating to the actuation wires. If excessive resistance exists,damage to the actuator wire may be indicated so that actuation mayresult in breaking of the actuator wire. If low resistance exists, theactuator wire may have a premature interface with ground so that currentapplied to the actuator wire will not result in wire heating. Oncecurrent is passed through the actuator wires, linear potentiometers 134measures the actual position of the sliding plate and provides positioninformation through an analog-to-digital converter 136 to a databus 138.Similarly, temperature sensor 130 measures temperatures at the actuatorwire and provides sensed temperature through an analog-to-digitalconverter to databus 138. In the example embodiment, since each actuatorwire set 56 has a separate resistance monitoring circuit, control forretraction and extension of keys may be managed separately based on theresistance of each actuator wire set.

Referring now to FIG. 10, a circuit block diagram depicts bothretraction and extension actuator wire sets protected by a commonresistance sampling circuit. Measuring resistance across both sets ofactuator wires does not allow for isolation to a particular actuator setif an unacceptable resistance is detected, however, the use of oneresistance measuring circuit reduces system cost and complexity. Forexample, if an actuator wire set proves unreliable for retraction, theneven if separate measurements are available the system cannot be usedfor extension since the keys will essentially be stuck in an extendedstate without the ability to retract the keys.

Although the present invention has been described in detail, it shouldbe understood that various changes, substitutions and alterations can bemade hereto without departing from the spirit and scope of the inventionas defined by the appended claims.

What is claimed is:
 1. An information handling system comprising: a mainhousing; processing components disposed in the main housing and operableto execute instructions that process information; a keyboard coupled tothe main housing, the keyboard having plural keys that move to acceptinputs, the keys biased to extend out of the housing and moving into thehousing in response to an end user press to accept end user inputs; oneor more actuator wires coupled to the keyboard and interacting with thekeyboard keys to selectively retract and extend the keyboard keys, theone or more actuator wires interacting with the keyboard keys byshortening in response to application of current; and a controllerinterfaced with the one or more actuator wires, the controller applyingthe current to retract and extend the keyboard keys based on one or morefirst predetermined conditions, the controller restricting applicationof current to the plural actuator wires based upon one or more secondpredetermined conditions.
 2. The information handling system of claim 1further comprising: a first shuttle coupled to a first set of the one ormore actuator wires and interacting with the keyboard keys to retractthe keys; and a second shuttle coupled to a second set of the one ormore actuator wires and interacting with the keyboard keys to extend thekeys.
 3. The information handling system of claim 2 wherein the firstpredetermined condition comprises a rate of movement of first and secondhousing portions relative to each other.
 4. The information handlingsystem of claim 2 wherein the one or more actuator wires comprise ashape memory alloy that transitions between austenite and martensitestates.
 5. The information handling system of claim 2 wherein the secondpredetermined condition comprises a temperature of the one or moreactuator wires.
 6. The information handling system of claim 5 furthercomprising an air moving device proximate the one or more actuatorwires, the air moving device providing a cooling airflow to the one ormore actuator wires when current is not applied to the one or moreactuator wires and the one or more actuator wires exceed a predeterminedtemperature.
 7. The information handling system of claim 6 wherein theair moving device comprises a piezo air moving device.
 8. Theinformation handling system of claim 6 wherein the air moving devicecomprises an electrostatic air mover.
 9. The information handling systemof claim 1 wherein the second predetermined condition comprises aminimum time period after the application of current to the one or moreactuator wires.
 10. A method for managing an information handling systemkeyboard configuration, the method comprising: monitoring at theinformation handling system for a first set of one or more predeterminedconditions associated with keyboard key position actuation; monitoringat the information handling system for a second set of one or morepredetermined conditions associated with restricting keyboard keyposition actuation; detecting at least one of the first set of one ormore predetermined conditions; and in response to the detecting,applying current to one or more actuator wires, the current shorteningthe wire length to actuate the keyboard keys to the associated position;wherein: detecting at least one of the first of one or morepredetermined conditions further comprises detecting rotation of housingportions relative to each other towards a closed configuration; andapplying current to the one or more wire actuators further comprisesshortening a wire length to retract the keyboard keys; and the first oneor more predetermined conditions further comprises a rate of rotationand applying current further comprises applying current a predeterminedtime before the rotation reaches the closed configuration based upon anangle of rotation and the rate of rotation.
 11. The method of claim 10further comprising: detecting at least one of the first of one or morepredetermined conditions further comprises detecting rotation of housingportions relative to each other towards away from a closedconfiguration; and applying current to the one or more wire actuatorsfurther comprises shortening a wire length to extend the keyboard keysafter the rotation of the housing portions stops.
 12. The method ofclaim 10 further comprising removing the current upon detection of thekeyboard key actuation completion.
 13. A method for managing aninformation handling system keyboard configuration, the methodcomprising: monitoring at the information handling system for a firstset of one or more predetermined conditions associated with keyboard keyposition actuation; monitoring at the information handling system for asecond set of one or more predetermined conditions associated withrestricting keyboard key position actuation; detecting at least one ofthe first set of one or more predetermined conditions; and in responseto the detecting, applying current to one or more actuator wires, thecurrent shortening the wire length to actuate the keyboard keys to theassociated position; detecting at least one of the second set of one ormore predetermined conditions, the second set of one or morepredetermined conditions including a temperature threshold; in responseto the detecting, restricting the applying current to the one or moreactuator wires until the second set of one or more predeterminedconditions changes; removing the current upon detection of keyboardactuation completion; and applying a cooling airflow to the one or moreactuator wires upon removing the current.
 14. A keyboard comprising:plural keys arranged to accept end user key inputs; first and secondshuttles interfaced with the keys, the first shuttle to move the keys toa retracted position, the second shuttle to release the keys to anextended position; a first set of plural actuator wires shortening inresponse to application of current to move the shuttle to the retractedposition; and a second set of plural actuator wires shortening inresponse to application of current to pull the sliding plate to theextended position; and a keyboard manager interfaced with the first andsecond sets of plural actuator wires, the keyboard manager applyingcurrent in response to a first set of predetermined conditions andrestricting the applying of current if the first set of predeterminedconditions occur during a second set of predetermined conditions. 15.The keyboard of claim 14 wherein: the first set of predeterminedconditions comprises an angular relationship between first and secondhousing portions and a rate of change of the angular relationship; andthe second set of predetermined conditions comprises a temperature ofone or more of the actuator wires.
 16. The keyboard of claim 15 furthercomprising an air moving device aligned to provide cooling airflow tothe one or more actuator wires if the temperature of the one or moreactuator wires exceeds a threshold.